This training grant application comes from the Curriculum in Toxicology, an interdisciplinary, interdepartmental and inter-institutional predoctoral and postdoctoral training program located at the University of North Carolina at Chapel Hill. The Training Program and its faculty benefit from being located in the Research Triangle Park area, an international center for toxicological research. The faculty of this training grant is a subgroup of the faculty of the Curriculum in Toxicology, and is drawn from the Schools of Medicine, Pharmacy, and Public Health at the University of North Carolina at Chapel Hill, as well as from federal research laboratories located in the Research Triangle Park. The faculty provides an unparalleled critical mass of nationally and internationally recognized experts in experimental toxicology, as well as exceptional new faculty who bring additional expertise and state-of-the-art technology. The Training Program covers many arenas in toxicology, but is linked thematically by a focus on the molecular and cellular mechanisms of action of toxic substances in mammalian systems and cell culture. Training and research is aided by extensive new facilities and research cores that provide trainees with state-of-the-art tools such as mass spectrometry, microarray, proteomics, and bioinformatics. The faculty provides predoctoral and postdoctoral research experiences in five major areas: Molecular Toxicology; Chemical Carcinogenesis; Neurotoxicology; Developmental Toxicology; and Pulmonary Toxicology. The goal of the Curriculum in Toxicology is to provide trainees, at both the predoctoral and postdoctoral levels, with broad-based training in toxicology, coupled with specific research experience guided by experienced and skilled mentors. The Training Program benefits from a continually improving system of research and career mentoring that has produced exceptional trainees for more than a decade. The career progress of the former trainees is consistent with the hypothesis that there is a continued need for well-trained and qualified toxicologists in academia, industry, and, government. The program's past and current record, in terms of high quality applicants, earned degrees, trainee publications, competitive awards, and employment history, provide strong evidence for continued excellence in the future. Finally, the Curriculum in Toxicology has had noticeable success with its efforts to open doors to careers in toxicology to qualified individuals from under-represented groups.